Supplemental Compensation Plans, Assumptions Used to Determine Benefit Obligations (Details) - Pension Plan [Member]	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Salary Continuation Plan and SERP [Member]
Assumptions used to determine benefit obligations [Abstract]
Discount rate used to determine net periodic benefit cost for years ended	2.30%	3.00%
Discount rate used to determine benefit obligations	2.60%	2.30%
Future salary increases	6.75%	6.20%
Directors' Retirement Plan [Member]
Assumptions used to determine benefit obligations [Abstract]
Discount rate used to determine net periodic benefit cost for years ended	1.30%	2.40%
Discount rate used to determine benefit obligations	2.10%	1.30%